STRUCTURAL AND ELECTROCHEMICAL STUDIES ON URANIUM(VI) NITRATO COMPLEXWITH TYL(PHENYL)-N,N-DIISOBUTYLCARBAMOYLMETHYLPHOSPHINE OXIDE IN NONAQUEOUS SOLVENTS

The structure of uranyl nitrate complex with CMPO yl(phenyl)-N,N-diiso butylcarbamoylmethylpho-sphine oxide] in solid state and in non-aqueou s solvents without containing free CMPO has been studied by using IR s pectrophotometer, C-13- and P-31-NMR. The carbonyl(nu(CO)) and phospho ryl(nu(PO)) stretching bands of coordinated CMPO were observed at lowe r wavenumber than the corresponding bands of free CMPO in both the sta tes. The C-13 and (31)p peaks assigned to the carbonyl carbon and phos phoryl phosphine of coordinated CMPO was detected in the lower field t han that of free CMPO. From these results; it was concluded that the u ranyl nitrate complex with CMPO in both the states has the structure w ith two nitrate and one CMPO coordinated as bidentate in the equatoria l plane of uranyl ion, i.e., UO2(NO3)(2). CMPO. Furthermore, the elect rochemical studies of UO2(NO3)(2).CMPO complex in CH3CN have been carr ied out using cyclic and normal pulse voltammetric methods. It was fou nd that the UO2(NO3)(2).CMPO complex is reduced to U(V) complex at aro und -1.22V vs. Fc/Fc(+) (ferrocene/ferrocenium) and that the resulting reductant is oxidized to U(VI) at around +0.04 V vs. Fc/Fc(+).